Mike is searching for a stock to include in his current stock portfolio. He is interested in Hi-Tech Inc.; he has been impressed with thecompany's computer products and believes Hi-Tech is an innovative market player. However, Mike realizes that any time you consider a technology stock, risk is a major concern. The rule he follows is to include only securities with a coefficient of variation of returns below

1.06.

Mike has obtained the following price information for the period 2012 through 2015

	Stock price
Year		Beginning		End
2012		$14.42		$22.01
2013		$22.01		$64.97
2014		$64.97		$71.21
2015		$71.21		$90.98

Hi-Tech stock, being growth-oriented, did not pay any dividends during these 4 years.

Calculate the standard deviation of returns over the past 4 years.

(Hint:

Treat this data as a sample.) ?